My bath has two taps and a plug hole.
[Ref: ZCSZ] © Kevin Stone
The cold tap on its own fills the bath in 18 minutes, the hot one in 15 minutes.
The plug hole can drain the bath in 10 minutes with the taps off.
How long will the bath take to fill if I leave both taps on with the plug left out?
Hint: How many baths could the cold tap fill?
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